Datasheet
LTM8032
18
8032fg
For more information www.linear.com/LTM8032
The most appropriate way to use the coefficients is when
running a detailed thermal analysis, such as FEA, which
considers all of the thermal resistances simultaneously.
None of them can be individually used to accurately pre
-
dict the thermal performance of the product, so it would
be
inappropriate to attempt to use any one coefficient to
correlate to the junction temperature versus load graphs
given in the LTM8032 data sheet.
A graphical representation of these thermal resistances
is given in Figure 6.
The blue resistances are contained within the µModule
regulator, and the green are outside.
The die temperature of the LTM8032 must be lower than
the maximum rating of 125°C, so care should be taken
in the layout of the circuit to ensure good heat sinking
of the LTM8032. The bulk of the heat flow out of the
LTM8032 is through the bottom of the module and the
pads into the printed circuit board. Consequently a poor
printed circuit board design can cause excessive heating,
resulting in impaired performance or reliability. Please
refer to the PCB Layout section for printed circuit board
design suggestions.
Finally, be aware that at high ambient temperatures the
internal Schottky diode will
have significant
leakage current
increasing the quiescent current of the LTM8032.
applicaTions inForMaTion
8032 F06
µMODULE REGULATOR
JUNCTION-TO-CASE (TOP)
RESISTANCE
JUNCTION-TO-BOARD RESISTANCE
JUNCTION-TO-AMBIENT RESISTANCE (JESD 51-9 DEFINED BOARD)
CASE (TOP)-TO-AMBIENT
RESISTANCE
BOARD-TO-AMBIENT
RESISTANCE
JUNCTION-TO-CASE
(BOTTOM) RESISTANCE
JUNCTION A
t
CASE (BOTTOM)-TO-BOARD
RESISTANCE
Figure 6